diff --git a/src/dwm.c b/src/dwm.c
index 36ddb6d..0b38b62 100644
--- a/src/dwm.c
+++ b/src/dwm.c
@@ -10,7 +10,6 @@
 #include "unit.h"
 #include "util.h"
 
-#include <locale.h>
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -268,20 +267,20 @@ static void (*handler[LASTEvent])(XEvent*) = {
 
 #include "config.h"
 
-/****************************
- * function implementations *
- ****************************/
+/************************************
+ * Private function implementations *
+ ************************************/
 
 #include "dwm/handlers.c"
 #include "dwm/layouts.c"
 #include "dwm/xerror.c"
 
+/***********************************
+ * Public function implementations *
+ ***********************************/
+
 int dwm_main()
 {
-	if (!setlocale(LC_CTYPE, "") || !XSupportsLocale()) {
-		fputs("warning: no locale support\n", stderr);
-	}
-
 	if (!(dpy = XOpenDisplay(NULL))) {
 		die("polytreewm: cannot open display");
 	}
@@ -306,6 +305,15 @@ int dwm_main()
 	return EXIT_SUCCESS;
 }
 
+bool dwm_has_locale_support()
+{
+	return XSupportsLocale();
+}
+
+/************************************
+ * Private function implementations *
+ ************************************/
+
 int applysizehints(
 	Client *c,
 	ClientGeometry client_geometry,
diff --git a/src/dwm.h b/src/dwm.h
index 988888b..49e987e 100644
--- a/src/dwm.h
+++ b/src/dwm.h
@@ -1,6 +1,9 @@
 #ifndef _DWM_H
 #define _DWM_H
 
+#include <stdbool.h>
+
 int dwm_main();
+bool dwm_has_locale_support();
 
 #endif // _DWM_H
diff --git a/src/main.c b/src/main.c
index fcf2689..7c14dae 100644
--- a/src/main.c
+++ b/src/main.c
@@ -2,6 +2,7 @@
 
 #include "dwm.h"
 
+#include <locale.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -18,6 +19,10 @@ int main(int argc, char *argv[])
 		die("usage: polytreewm [-v]");
 	}
 
+	if (!setlocale(LC_CTYPE, "") || !dwm_has_locale_support()) {
+		warning("no locale support");
+	}
+
 	return dwm_main(argc, argv);
 }
 
@@ -45,3 +50,15 @@ void die_perror(const char *const fmt, ...)
 
 	exit(EXIT_FAILURE);
 }
+
+void warning(const char *const fmt, ...)
+{
+	fputs("WARN: ", stderr);
+
+	va_list ap;
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+
+	fputc('\n', stderr);
+}
diff --git a/src/main.h b/src/main.h
index 79699f8..f9a0d82 100644
--- a/src/main.h
+++ b/src/main.h
@@ -3,5 +3,6 @@
 
 void die(const char *fmt, ...);
 void die_perror(const char *fmt, ...);
+void warning(const char *fmt, ...);
 
 #endif // _MAIN_H